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  • 0 to 14 pH measuring range
  • Chemically resistant KYNAR
  • Rugged, quick change, quick clean
  • Max temp: 266°F/130°C at 40 psig/276 KPa
  • Max pressure: : 150 psig/1035 KPa at 158°F/70°C
  • Model RBI-546:
    • 3/4in MPT threaded nose
    • Submerged; 3/4in MNPT threaded top
  • Model RBI-547:
    • 1in MPT process fitting or, 1¼ and 1½in ball valve assemblies
    • 1in MNPT process fitting, into 1in FNPT coupling or ¾in submersion extension pipe

The Rosemount Analytical RBI pH Sensor is designed for extended sensor life when used in applications with sulfides which are typically found in scrubbers. The Model RB is made with chemically resistant KYNAR. Optional installation methods allows standardization of entire plant with a minimum of sensor part numbers.

They're built with a Kynar body and is designed in two configurations. The 546 sensor is housed in a fully encapsulated body for use in pipe tees or submersed in a tank. The 547 is the ball valve retractable version; the sensor body can be replaced and the titanium sensor sheath assembly (sold separately) can be reused. Both sensor types are built with a high performance J glass, notched tip with a Teflon junction, and a PT100 RTD. The integral cable is prepared with tinned leads for easy wiring.


Rosemount Analytical 23646-01 Extension Cable
11-cond shielded extension cable
Rosemount Analytical 11-conductor Extension Cable


Rosemount Analytical pH Buffer Solutions
pH buffers for the precision calibration of pH meters


Please consider these optional accessories.

Rosemount Analytical O-ring / EPDM
Quantity of 4, 2-214, EPDM, includes lube
Rosemount Analytical 9550220 O ring
2-214, Kalrez, for Process Connector
Rosemount Analytical 23166 Connector
1 x 1in with o-ring groove, in 316 SS or titanium
Rosemount Analytical 23555-00 Junction Box
Compatible with models 54, 5081, 1055 & Xmt preamplifiers
Rosemount Analytical Junction Box Sensor Head
Includes preamplifier, for 54 & 3081
Rosemount Analytical Ball Valve Assembly
1.5in, 316 stainless steel, process connector required
Rosemount Analytical BNC Adapter
BNC Adapter for Model 396P and 396PVP
Rosemount Analytical 99CC Calibration Certificate
One certificate per lot at standard factory ranges only, includes the model, serial and/or tag numbers (does not include actual test data)
Rosemount Analytical Electronic Calibration
Certificate for specific unit, includes model, serial and/or tag numbers, test standards, NIST report numbers, & the actual test data
Rosemount Analytical Certificate of Origin
Original certificate of origin with chamber of commerce stamp


This product can be used in the following applications:

Application Notes

Here's how some of our customers used this product.

Monitoring the pH of a Wet Scrubber

The Background: Our customer is an industrial facility who’s process creates nitrogen oxide as a byproduct. Nitrogen oxide is a powerful pollutant that needs to be removed from the plant’s emissions before they are released to the atmosphere. It is removed using a wet scrubber. The customer needs an effective means of monitoring the pH of the wet scrubber to ensure the proper concentration of the chemicals used to remove the nitrogen oxide.

The Problem: The wet scrubber uses sodium hydroxide and sodium hydrosulfide to remove the nitrogen oxide. Both of these compounds are powerful alkalis meaning the pH can be as high as 12. A pH that high cannot be accurately measured with many pH electrodes. The pH is also high enough to damage electrodes.

The Solution: We recommended the Rosemount Analytical RBI pH Sensor which is designed for challenging environments. The RBI has a measuring range up to 14 pH and has a chemically resistant KYNAR body. The RBI includes has 5 junctions to resist poisoning extend sensor life.